Figure6.16Methods of(a)Thepourplatemethod(b)Thespreadplatemethodpreparingplatesforplatecounts.1.0or0.1ml0.1mlHow do pour plates and spreadplates differ?InoculateInoculateplateemptyplatecontainingsolidmediumBacterialdilutionAddmeltednutrientagarSpreadinoculumoversurtaceevenlySwirltomixColaniesColoniesgrowgrowinandonlyonsurfaceonsolidifiedofmediummedium
2Growth Curve2.1 Synchronous growth/同步生长(1) Environmental condition induction method(2)Mechanical screening/机械筛选法
2.1 Synchronous growth/ 同步生长 (1) Environmental condition induction method (2) Mechanical screening/机械筛选法 2 Growth Curve
膜洗脱法Helmstetter-CummigsS
Helmstetter-Cummigs 膜洗脱法
Flaskinoculated+Samplestakenatequallyspacedintervals(0.1ml)300min420min480min540min60min120min180min240min360min600min0.1ml500mlSampleisdiluted inliquidagarmediumand pouredorspreadoversurfaceofsolidifiedmediumPlatesareincubatedNonecoloniesarecountedNumberofO'37132345801352301colonies(CFU)per0.1mlTotal cellO"5,00015,00035.00065.000115,000225,000400,000675,0001,150.000populationinflaskZeroCFUsonlymeans thattoofewcellsarepresenttobeassayed
• 2.2 Typical growth curve for single-celled microorganisms
: 2.2.1 Lag phase When microorganisms are introduced intofresh culture medium, usually no immediateincrease in cell number occurs. This period iscalled the lag phaseStationaryphaseaaExponential (log)phateDeathphaseLagphaseTime
• 2.2.1 Lag phase • When microorganisms are introduced into fresh culture medium, usually no immediate increase in cell number occurs. This period is called the lag phase